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Solvent-Dependent Green Synthesis of ZnO Nanopowders Using Mitragyna speciosa Leaf Extract: Impact on Piezo-Photocatalytic and Antibacterial
(2026-07-01)
Sanyen, Thanyapa
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Songpanit, Maneerat
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Kansaard, Thanaphon
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Wirunchit, Supamas
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Chutipaijit, Sutee
ZnO nanopowders were synthesized via a solvent-mediated green route using Mitragyna speciosa Korth. leaf extract as reducing and stabilizing agents. Deionized water and methanol were employed to tailor the phytochemical composition of the extracts. The influence of extract concentration (5–20 mL) and solvent polarity on structural, morphological, and functional properties was systematically investigated. Structural analyses confirmed the formation of Zn-O bonds and a phase-pure hexagonal wurtzite ZnO without secondary phases. Surface morphology revealed solvent-dependent morphological evolution toward spherical shapes and reduced aggregation in the methanol-derived system. For antibacterial activity, green ZnO nanopowders demonstrated enhanced biocidal effects against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, comparable to that of commercial ZnO nanoparticles. Enhanced piezo-photocatalytic degradation of rhodamine B was achieved under combined light and ultrasonic irradiation, with superior performance observed for methanol-derived ZnO. This enhancement is attributed to the synergistic interplay of solvent-induced defect states, reduced particle size, and piezoelectric field-driven charge separation. Scavenger analysis confirmed that superoxide radicals ((Formula presented.)) dominate the degradation pathway by green-synthesized ZnO nanopowders prepared from different solvent extracts. Thus, a correlation between solvent-mediated phytochemical environments and piezo-photocatalytic activity provides new insights for the design of sustainable, high-performance ZnO-based catalysts.
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Biomass-Based Synthesis of Tunable Photoactive Bimetallic Nanoparticles for Antibacterial and Catalytic Applications
(2025-09-12)
Jaroensin, Punsachon
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Nunsap, Janistar
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Khuanchom, Vipada
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Hararak, Bongkot
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Lueangjaroenkit, Piyangkun
The green synthesis of noble metal nanoparticles has gained increasing attention due to cost-effectiveness and environmental friendliness. This research aims to develop an efficient method to synthesize lignin-capped gold–silver nanoparticles (Li-GS NPs). Lignin has recently been reported to function both as a reducing agent and as a capping agent in the synthesis of metal nanoparticles. These Li-GS NPs were successfully synthesized via galvanic replacement by using lignin-capped silver nanoparticles (Li-Ag NPs) as a precursor. Lignin extracted from various sources, bagasse (BG), pararubber woodchip (PRW), and palm kernel shells (PKS) were used to investigate the effect of different functional group compositions on the nanoparticle formation. Li-Ag NPs were uniformly synthesized and transformed into well-dispersed Li-GS NPs via galvanic replacement with KAuCl<inf>4</inf>, as indicated by an LSPR shift from 420 nm to 550–600 nm. Li-Ag NPs ranged from 8 nm to 28 nm, while Li-GS NPs exhibited a broader size distribution, reflecting gold-induced growth and morphological variation. Li-GS NPs demonstrated stronger antibacterial activity against both Gram-positive and Gram-negative bacteria, with Ag contributing significantly to bactericidal effects. Additionally, Li-GS NPs exhibited high catalytic efficiency in 4-nitrophenol reduction, completing the reaction within 1 min. Importantly, using lignin as both a reducing and a stabilizing agent is expected to significantly reduce costs and minimize the use of hazardous chemicals.
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Antioxidant and Antibacterial Activities of Jasminum officinale L. f. var. grandiflorum (L.) Kob. Leaf Extracts
(2024-05-01)
Charoenying, Patchanee
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Laosinwattana, Chamroon
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Chotsaeng, Nawasit
The investigation of phytochemicals and their effects on plants is currently receiving significant attention due to the well-known fact that plants contain secondary metabolites that have high levels of usefulness in various applications. These applications include food additives, biopesticides, and pharmaceuticals. In a recent study, we thoroughly examined the total phenolic content (TPC), and the antioxidant, and antibacterial properties of Jasminum officinale L.f. var. grandiflorum (L.) Kob. (also known as Spanish jasmine) leaf extracts, providing valuable insights into its potential benefits. Our study performed a crude methanol (ME) extraction of Spanish jasmine leaves with acid-base solvent partitioning, resulting in an acidic fraction (AE), a neutral fraction (NE), and an aqueous fraction (AQ). The Folin-Ciocalteu method was used to determine the TPC of the extracts. The AE fraction displayed the highest TPC (79.8±0.61 mgGAE/g dry weight), followed by the NE and AQ fractions. The extracts were further evaluated for their antioxidant activity using the DPPH assay. The AE fraction had the highest antioxidant activity with an EC<inf>50</inf> value of 4.6±0.40 µg/mL. The main active compound, oleuropein, was isolated and determined using spectral data. The isolated compound displayed excellent antioxidant activity with an EC<inf>50</inf> value of 13.0±0.06 µg/mL. Moreover, the antibacterial activity of the Spanish jasmine leaf extracts was calculated using the disc diffusion method based on the minimum inhibitory concentration. The AE fraction exhibited activity against the Gram-negative bacteria, Vibrio parahaemolyticus, with a MIC value of 0.78 µg/mL. The AE fraction also displayed the highest degree of activity against Staphylococcus strains, including drug-resistant strains (MRSA and VRSA), with a MIC range of 0.39-12.5 µg/mL. It is important to highlight that the AE fraction demonstrated the highest level of activity against all VRSA strains tested despite their resistance to vancomycin and oxacillin. These findings strongly indicate that Spanish jasmine leaves possess potent natural antioxidant and antibacterial properties, positioning them as a highly promising plant source.
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A Shear-Thinning, Self-Healing, Dual-Cross Linked Hydrogel Based on Gelatin/Vanillin/Fe3+/AGP-AgNPs: Synthesis, Antibacterial, and Wound-Healing Assessment
(2023-12-01)
Talodthaisong, Chanon
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Patramanon, Rina
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Thammawithan, Saengrawee
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Lapmanee, Sarawut
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Maikaeo, Lamai
A shear-thinning and self-healing hydrogel based on a gelatin biopolymer is synthesized using vanillin and Fe<sup>3+</sup> as dual crosslinking agents. Rheological studies indicate the formation of a strong gel found to be injectable and exhibit rapid self-healing (within 10 min). The hydrogels also exhibited a high degree of swelling, suggesting potential as wound dressings since the absorption of large amounts of wound exudate, and optimum moisture levels, lead to accelerated wound healing. Andrographolide, an anti-inflammatory natural product is used to fabricate silver nanoparticles, which are characterized and composited with the fabricated hydrogels to imbue them with anti-microbial activity. The nanoparticle/hydrogel composites exhibit activity against Escherichia coli, Staphylococcus aureus, and Burkholderia pseudomallei, the pathogen that causes melioidosis, a serious but neglected disease affecting southeast Asia and northern Australia. Finally, the nanoparticle/hydrogel composites are shown to enhance wound closure in animal models compared to the hydrogel alone, confirming that these hydrogel composites hold great potential in the biomedical field.
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EVALUATION OF BIOACTIVITIES OF EICHHORNIA CRASSIPES PARTS EXTRACTS
(2023-01-01)
Sriwatcharakul, S.
The aims of this research to study bioactivity of leaf, stolon and root extracts from Eichhornia crassipes that is an alien plant in Thailand. The determination of phytochemical exhibited that! leaf extract had the highest of flavonoid and tannin as 207.60 mg QE/g extract and 72.40 mg TAE/g extract, respectively. And root extract showed the highest level of anthocyanin as 17.53 mg cyanidin-3-glucoside/ l extract, while total phenolic contents not significant between leaf, root and stolon extract. To analyze antioxidant activity found that stolon extract had the highest scavenging activity that IC50 was 3.23 mg/ml. The antibacterial activity exhibited that stolon extract had the lowest minimum bactericidal concentration than other two extracts against Pseudomonas aeruginosa TISTR 781, Escherichia coli TISTR 780, Staphylococcus aureus TISTR 1466 and Yersinia enterocolitica. According to the phytochemicals and bioactivities results, stolon and leaf extracts of E. crassipes have potential for remedy and health care aspects to add value of this plant.
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Cytotoxic and antibacterial depsidones from the endophytic fungus Chaetomium brasiliense isolated from Thai rice
(2022-01-01)
Promgool, Trinop
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Kanokmedhakul, Kwanjai
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Leewijit, Thianrat
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Song, Jiaojiao
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Soytong, Kasem
Four new depsidones, mollicellins V-Y (1-4), together with eight known depsidones (5-12) were isolated from the endophytic fungus, Chaetomium brasiliense, detached from stems of Thai rice. Their structures were determined by extensive spectroscopic methods. Mollicellins X, H, and F (3, 8 and 10) showed potent cytotoxicity against the human oral epidermoid carcinoma (KB) cell line, and mollicellin F (10) also showed a potent cytotoxicity against the human hepatocellular carcinoma (HepG2) cell line. Besides, mollicellin B (11) exhibited cytotoxicity against the colorectal adenocarcinoma (HT-29) cell line. Moreover, most of the isolated depsidones displayed potent antibacterial activity against Gram-positive bacteria, Bacillus cereus and Bacillus subtilis, and several of them showed moderate activity against Methicillin-resistant Staphylococcus aureus (MRSA) and clinical isolates of S. aureus. In addition, a few of them also showed moderate activity against a Gram-negative bacteria Pseudomonas aeruginosa.
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BIOACTIVITIES EVALUATION OF THE USELESS PARTS OF ACACIA AURICULIFORMIS EXTRACTS
(2022-01-01)
Sriwatcharakul, S.
This research aims to study bioactivity of leaf, inflorescence and branch extracts from Acacia auriculiformis that has been used as forest plantation in Thailand. The extracts were evaluated of antioxidant activities by DPPH scavenging method, branch extract gave the best 50 percent Inhibition Concentration (IC50) at 19.36 mg/ml. To find out total phenolic contents, branch extract had the highest total phenolic contents at 597.22 mg GAE/g extract. Antibacterial studied of extracts against five bacterial strains; Escherichia coli TISTR 780, Staphylococcus aureus TISTR 1466, Micrococcus luteus TISTR 2374, Bacillus cereus TISTR 687 and Xanthomonas campestrispv.campestris TISTR 2065. The result of antibacterial activity using agar well diffusion method was found that all of extracts could not inhibit the growth ofE. coliwhileleaf, inflorescence and branch extract could inhibit the growth ofother four bacterial strains S. aureus, M. luteus B. cereus and X. campestrispv campestris. And MIC studied found thatinflorescence extract used the lowest concentration to inhibit the growth ofS. aureus, M. luteus, B. cereus and X. campestrispv campestris. According to the bioactivities results, branch and inflorescence extracts of A. auriculiformis have potential for remedy aspects to add value of this plant.
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Bioactive xanthoquinodins and epipolythiodioxopiperazines from Chaetomium globosum 7s-1, an endophytic fungus isolated from Rhapis cochinchinensis (Lour.) Mart
(2020-02-16)
Tantapakul, Cholpisut
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Promgool, Trinop
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Kanokmedhakul, Kwanjai
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Soytong, Kasem
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Song, Jiaojiao
A new xanthoquinodin B9 (1), together with two known xanthoquinodins, xanthoquinodin A1 (2) and xanthoquinodin A3 (3), three epipolythiodioxopiperazines, chetomin (4), chaetocochin C (5) and dethio-tetra(methylthio)chetomin (6), and four other compounds, chrysophanol (7), emodin (8), alatinone (9), and ergosterol (10) were isolated from the endophytic fungus Chaetomium globosum 7s-1, isolated from Rhapis cochinchinensis (Lour.) Mart. All isolated structures were established based on their spectroscopic data analyses. Compounds 1–6 showed antibacterial activity against Gram positive bacteria with MICs ranging from 0.02 pM to 10.81 µM. Compounds 1–6 also exhibited cytotoxicity against KB, MCF-7 and NCI-H187 cancer cell lines (IC<inf>50</inf> 0.04–18.40 µM). However, they were cytotoxic towards a normal cell line (Vero cell) with IC<inf>50</inf> values ranging from 0.04 to 3.86 µM.

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